A Research into Extra-thick compound mudstone roof roadway failure mechanism and security control

Using roof accident cases, this paper analyzes the characteristics of extra-thick compound mudstone roof surrounding rock in the laboratory, and then it studies the failure characteristics and instability mechanism of the roof through numerical simulation, together with field measurement of the digging roadway surrounding rock deformation and bolt support load. The results show that roadway support structure is rational and four solutions are proposed for reinforcing surrounding rock timely, enlarging anchorage range, improving the support stiffness of lower rock stratum, and disposing the bolt and anchor cable along the cracks to improve the intensity at the top right angles of the roadway. This study might provide scientific basis for the similar compound roof roadway support in the future.